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HP-Collection · (This post was last modified: 05-24-2017 09:10 PM by HP-Collection.)

Guys, does someone of you know why there are different labels on the left side of the HP-18C. Here are two different versions I just found during the last month in the bay....

(Sorry, updated the post as there was an error on my side)

SlideRule · 05-24-2017, 10:06 PM

Key observation - CHARY - an aftermarket vendor.

BEST!
SlideRule

**rprosperi** · 05-25-2017, 01:26 AM

Chary made overlays for many of the financial machines; probably the earliest was the 12C, however since that model was around so long, it's hard to tell. Overlays for the 12C could have been introduced 5 years before the 18C was launched, or 20+ years after the 18C was discontinued...

But I would guess that the 12C versions were first.

Thanks for sharing that Matthias, I've not seen 18C overlays before.